promoting us

The below Article is from today's On-line Business Spectator. Why isn't our company promoting itself and it's technology in similar ways?? ie, Get a "Professor" to relate our technology to "emissions control", throw in some really big numbers and spread it around the media, government etc.

Cleaner coal? The answer lies below
Published 9:34 AM, 26 Jul 2011
Updated 10:26 AM, 26 Jul 2011
Tags
Australia, coal, emissions reduction, geothermal, thermal efficiency, Smart EnergyLogin or register to post comments
Giles Parkinson
Just over two years ago, I concluded an article for Business Spectator with the rather flippant remark that if the executives of emissions-intensive generators were really serious about reducing emissions, then they?d reverse their BMWs and Audis out of the executive car park and drill down to tap into the geothermal resources that lie beneath.

It turns out it wasn?t such a silly idea.

Professor Behdad Moghtaderi, the deputy-Director of the Priority Research Centre for Energy at the University of Newcastle, has filed patents over a new system that would allow coal-fired generators to use geothermal power to pre-heat water and improve the thermal efficiency by as much as 30 per cent ? with corresponding reductions in coal use and emissions.

Moghtaderi says most coal-fired power stations are situated in areas that have good geothermal resources. The coal deposit often acts as a thermal blanket over hotter rocks below. The sort of heat necessary to make this system work ? around 120?C to 150?C ? can probably be found at relatively shallow depth using conventional technology.

Coal-fired power stations create electricity by boiling water and creating steam to drive a turbine. To try and improve the efficiency of that system, some of the steam is diverted to ?pre-heat? the water. Moghtaderi suggests using geothermal heat to replace that diverted steam. He says this could add another 12 per cent to the normal rate of thermal efficiency at these plants ? from around 35 per cent to the high 40s.

?That is a massive increase,? he says. It would also lower the emissions profile of some coal-fired power stations down towards those of gas-fired generators. Some initial estimates prepared by Moghtaderi and his partner in the concept, Brad Mullard, the executive director of mineral resources, industry and development within the NSW government, suggest major reductions of CO2 and sulfur dioxide and nitrous oxides, as well as heavy metals.

The numbers suggest a 10 per cent gain in thermal efficiency across the NSW industry would avoid 89 million tonnes in CO2 emissions over 10 years, 250,000t of SO2 and 175,000t of N2O, as well as delivering coal savings of $1.44 billion, and $2.24 billion in carbon credits. A 20 per cent gain in thermal efficiency would double those achievements.

Moghtaderi says it is a relatively simple concept and ? despite the cost of drilling and of retrofitting plants ? it is likely to be much cheaper than some of the other alternatives, particularly carbon capture and storage, where coal-fired producers are also likely to need to burn 30 per cent more coal to make the system work.

The idea is similar to the solar-booster technology that is installed at the Liddell power station in the Hunter Valley, and is about to be repeated at a larger scale at the Kogan Creek power station in Queensland. The advantage of geothermal over solar is that it can operate all night long ? the experience at Liddell is of less than 25 per cent capacity ? and probably at significant lower cost.

Indeed hybridisation ? be it solar/coal, geothermal/coal, solar/gas ? seems to be all the rage. Some green groups and advocates of 100 per cent renewable technology don?t like it, but it?s generating a lot of interest in the industry because it lowers costs, means that existing assets retain value, and also exploits resources such as solar and geothermal that do not yet have the operating cost profile to flourish on a stand-alone capacity.

Moghtaderi is generating interest not just from generators but also some coal miners. It seems that now a carbon price is to be introduced, rather than sitting on a stranded asset and bleating about it, some are now keen on taking proactive action. He hopes to secure seed funding for the concept soon, and then begin proving it. Once that is done, the actual implementation of a project could take less than a year.

There may be another incentive for coal suppliers ? many provide coal to local generators at a significant discount to the export price ? if they can satisfy the local demand with less coal, it frees up more to be exported overseas.

Last year, a survey by geothermal consultants based on oil and gas drilling in the Latrobe Valley suggested an extensive resource of geothermal energy ? with temperatures of 150?C or more ? lies beneath the massive brown coal generators and the 400m of brown coal reserves. Hot Dry Rocks also plans to pilot a small-scale 500kW geothermal power plant in the Latrobe Valley, using technology developed by Melbourne-based car air conditioning specialist Air International Thermal Systems to build cheap plants that can tap into shallow aquifers heated to around 80-90?C.

The nature of the technology means that it will work best where coal-fired power stations are located adjacent to their coal deposits, and therefore the geothermal resources. Moghtaderi estimates that up to 30 per cent of US coal-fired plants may be similarly located above geothermal resources, with around 20 per cent in China and 15 per cent in India. That still equates to around 15 per cent of global coal-fired generation assets.